A curvaceous model and bodybuilder says she was viciously attacked by a drunken Wall Street bigwig after she refused demands to drive him home in the middle of the night, she claims in a $100,000 Manhattan Supreme Court lawsuit.

Sahara Walsh, 29, of Harlem, claims Quintano Downes “apparently intoxicated, jumped into the back seat of the vehicle with an open plate of food” at around 3:50 am on April 28.

The former Equinox trainer describes herself as a “body model” who competes in bodybuilding competitions. She was in the car with a friend outside her Lenox Avenue home.

When she complained about the intrusion Downes, 46, a director at the financial firm Kipling Jones & Co., “started to punch [her] with a closed fist, dragged her out of the car by her hair and continued to stomp” her, the suit claims.

He then allegedly “ripped [her] blouse off exposing her breast to the public and continued to drag [her], causing her to lose her shoes.”

A witness told the Manhattan District Attorney’s Office that Downes pummeled Walsh’s face “and kicked her about her body, causing bleeding and laceration to her face, legs, and arms,” according to court papers.

Walsh is out of town, but her attorney, Edgar De Leon, said that his client did not know her accused attacker.

“This hedge-fund guy is pretty intoxicated; when they tell him to get out of the car, he just turned on Walsh, pulled her out of the car and continued hitting her until the police responded,” De Leon said.

“She’s very traumatized by the whole ordeal. It was so unexpected and pretty vicious.”

Walsh said her physical injuries —including a black eye, bruises on her legs and a missing clump of hair — have caused her to lose modeling work.

A criminal case is pending against Downes, who recently bought a $2 million brownstone in Harlem with his wife.

He also plans to open a European-style frozen-yogurt joint, called Pa-Paya Seed, on Lenox Avenue between 118th and 119th streets.

He declined to comment outside the store yesterday but his attorney, Bruce Roistacher, told The Post that his client “denies all the charges.”

Roistacher alleged that Walsh’s companion, an acquaintance of his client, assaulted him and he was simply defending himself against the attack. He declined to name the woman or say how his client was injured.

Downes is facing harassment and assault charges and is due back in court in August.